Mixing apparatus



4 Sheets-Sheet l rllln- A. B. SMITH ET AL MIXING APPARATUS Filed Sept. 24, 1927 March 18, 1930.

March 18 1930. A. B; SMITH ET AL MIXING APPARATUS Filed se th24, 1927 4 Sheets-Sheet 2 March 18, 1930.

A. B. SMITH ET AL MI XING APPARATUS Filed Sept. 24, 1927 4 Sheets-Sheet 3 March 18, 1930. A. B. SMITH ET AL MIXING APPARATUS Filed Sept. 24, 1927 4 Sheets-Sheet 4 ZA/ VENTO 7m Patented Mar. 18, 1930 i I p UNITED STATES PATENT oFFICEQ-y ALFRED BARTLETT SM TH AND CLIFFORD ROSS SMITH, or .WOLVERHAMPTON,

ENGLAND MIXING APPARATUS Application filed September 24, 1927, Serial No. 221,677, and in Great Britain October 1926.

, Our invention relates to a method and A further preferred feature of the invenmeans for mixing pulverulent or granular tion is the provision of means in the appa materials and/or for mixing or blending ratus to toss or throw the materials, after such materials with liquids or with semithe squeezing action, to break upvthe mass solid substances. and facilitate intimate mixing.

The invention is more particularly in- In order that the invention may be readil tended for mixing sand with oil, compounds, understood, it will be hereafter described as A clays, or other binding materials, for coreapplied by way of example to ahorizontal making and other foundry purposes, but is pan type mixer by theaid of the appended capable of a wider use in mixing operations, drawings. as for example in mixing sand or crushed Figure 1 is a plan of this apparatus. Y chippings or slag with bituminous materials Figure 2 is a vertical section thereof. for road making and like purposes, or in Figure 3 is a detail section shewing a dis; dough mixing, clay preparation and similar chargedoor. i

operations. Figure l is a plan of a fixed pressure mem- 60 The object of, the invention is to obtain ber or plate. 7 I A an eflicient coating or blending of the indi- Figures 5 to 10 are sections of the plate vidual grains of the sand or other material taken on lines correspondingly num er i with the binding agent or other ingredient Figure 4. v A

of the admixture. Figure 11 is a plan of one of the rotating The invention primarily consists in the sweeps,;and 1 v method of mixing and blending the materials Figures 12 and 13 are sections thereof on by the co-operation of inclined or curved lines 12-12, and 13-13 of Figure 11. I moving and fixed, or relatively vmoving, In the illustrated, and preferred-,form of V members, in a suitable apparatus, which apparatusfor carrying out the method,asta- 70 carry the material and throw and roll it about tionary pan a of suitable dimensions is em-* the container and in addition squeeze it in ployed, which may be open at its upper end, Wedge-like pockets or passages formed by. the and has. ata suitable point at-or nea'r its circo-operating members, eventually shearing cumference a-disoharge opening?) in its base the mass therein. I arranged near the peripheryof the pan and 75 As a result of this action, after only-a controlled by a suitably operable-slide or relatively short treatment every particle of shutter 0. The edge of the discharge open-1 the materials is dealt with individually, and, ing is preferably backwardly inclined and. in the case of blending powdered or granular the door oppositely inclined to render the I 3:, materials with liquids or semi-solids, an even device self cleaning as far as possible and distribution 'of .the liquid or semi-solid is prevent choking with sandor the like. 'The efiected and the particles or grains of the upper edges of the openingand door are material under treatment are fully and comslightly bevelledas shewn in Figures 3,,as pletely coated. 4 this we" find assists in making a sand tight 40 The invention also comprises. apparatus closure. A vertical shaft or revoluble sleeve for carrying out the method, in which sweeps d arranged axially of the pan, and driven or blades act in conjunction with pressure in any suitable manner, as for example 'by surfaces, either fixed or relatively moving, so worm and worm-wheel from the driving shaftthat the materials are squeezed between the e, carries a, series of horizontal. blades or 45 sweeps andpressure surfaces. A r Y sweeps Each sweep f is arranged to.form 90 V rial from the base of the pan until it climbs and rolls over the elevated rear or trailing at its leading edge or face a suitable angle with the base of the pan and being inclined rearwardly in the direction of motion of the shaft or sleeve cl. Arranged above the upper edge of the shaft or sleeve (Z, and rotatable therewith, is a distributing dome orspreader toincline or curve backwardly from the-true radialline; The action of these sweeps,therefore,"is to press forward and raise the mateedges, and at the same time, by reason of the angle at which the sweeps are set,*they't'end to throw or force the material radiallyoutwardstowards the circumferential wallof thefp'anf p i I "In the: upper part" of the pan a, there are secured to the circumferential wall, and ex= zsatending inwardly therefrom, a series of fixed pressure "surfaces in the form of blades or plates hof novel formation; The entrance edges of thesetplates, which are first en'- countered by the materialas it is carried arethe highesu-and as ;the exit ends are 'appreached, the under surfaces of the plates contact with the pan'wall in a'substantially' gradually lower and preferably also approach the centre sleeve; or shaft d until they Lterminate in a horizontal plane lying at -a slightly higher level than the plane in which therear'or trailing edges of the'swee'ps 'ro- The entrance edge is preferably-curved ,backwardly as it approaches the centre of the apparatus to tend to turn materials impinging on it inward toward the centre= The under, and operative, face of each fixed blade or plate, is preferablycoinposed sof twor or'more inclines or fcurves, a more abrupt inclined face 71 near the entrance edge giving way to a more gradualwedging face 9 towardthe exit edge. The particular shape ofthe blades in the presentexample'is shown y by a series of sections, Figs; '5 to 10.

In the apparatus so far made by us, these blades or plates have been cast hollow wit-h V a curved top' surface to; shed or deflect, into thepan, any material falling on it. I

"As the material is thrown outwards by the sweeps itis turned over upwardly and'in-[ wardly by-the'fixedblades or plates, and by spiral manner, and as a sweep approaches the -,hor1zontal'lowe'r edge'of a plate it'tendsto force the material into, and through, a space of gradually diminishing area, constituted by '1 the slopinggface of the fixed plate and the pan 'base,, thus exertinga powerful squeezing -l I V E 1 1-5;. 2.:1: leadlng edges, the said surfaceszbecomingine round by the action of the moving blades,

When mixing sand with oil or compound, the mixture begins to form a bond, or to stifien, as the particles of sand become coated, and while the materials at first appear to be thrown outwardly and returned in a spiral direction to be squeezed and then tossed over the rotary sweep, as a bond or complete mixture takes'place, the materials seem to rise in masses or chunks over the rotary sweep and to drop over the back of the sweep and break up, giving a further mixing action.

The combination of movements thus given to, and of the actions exerted upon, the ma- I .terial by the co-operation of the sweeps and fixed blades, produces a very intimate 'ad- 'mixture and blending.

In mixing sand with oils, clays, or binding compounds for foundry purposes, an intimate and even admixture is essentia'lwif the requisite bond is to be obtained, and we have been able to achieve the desiredjresul-ts in our improved apparatus ifi'a rapid and economical manner. 1 I r V v I 7 Although the particular embodiment above described constitutes a good practical form of the invention, it will be apparent that modifications may be made.

In one arrangement, both tions andat similar-or suitably proportionate speeds. In another arrangementflve may rol' tate the pan carrying the plates, the sweeps being statlonary.

It will be apparent' thatthemeans em ployed to drive the movingpart, or parts, asv

either by hand or power, may be provided 1 inplace of the screwactuated discharge slide c to open and close the discharge opening atthe desired times, and more than'one discharge opening maybe provided if; desired.

If necessary, a pivoted striker may be provided in the wall of the pan adjacent the disany material sweeps as ischarge takes charge opening a to break 11 adhering to the place,- 1

We claim 1. Apparatus.

drical container, a spindle rotatable about a the plates and the s'weepsfmay revolve, in differentdirea:

for mixing finely divided I materials with a binder,comprising a y1invertical axis in the centre of the container,

a domed distributing member. above ;the

centre of the container,backwardly ra'kedi and inclined blades carried by and rotating with the spindle and extending substantially from it to the inner face of thecontainer, fixed members extending fIOlllllllIGlIll'lSljEfElfiG of the container substantially to the spindle,

and provided with ressure surfaces. fora wardly curved towar s the wall of the containerianddownwardlyinclined'from'their creasingly close to and co-operating with the rotating blades to form squeezing pockets without lateral escape, and means for discharging the mixed materials from the container.

2. Apparatus for mixing finely divided materials with a binder, comprising a cylindrical container, means for discharging mixed materials from the container, a spindle rotatable about an axis in the centre of the container, backwardly raked and upwardly inclined blades carried by and rotating with the spindle and extending from it approximately to the inner face of the container, fixed members having forwardly curved and downwardly inclined pressure surfaces secured to the side walls of the container and extending inwardly approximately to the spindle, the upper edges of the blades being arranged so that they just clear the lower edges of the pressure surfaces and the blades as they rotate co-operating with the pressure surfaces to form Wedge-like pockets between them in which the materials in the container are squeezed with progressive pressure without opportunity for lateral escape they are carried around by the blades.

3. Apparatus for mixing finely divided materials witha binder,comprising a cylindrical container, a spindle rotatable about an axis in the centre of the container, blades carried by the spindle and extended into close proximity to the inner wall of the container and rearwardly raked and upwardly inclined from their leading edges to their rear edges and adapted to thrust materials in the container upwardly and work them away from the centre, fixed members extending substantially from the inner face of the container to the spindle and having surfaces adjacent to and co-operating with the rotating blades, these surfaces being inclined downwardly and away from the edge which first meets the materials and adapted to press the materials downwardly and towards the centre of the container under progressive pressure and without lateral escape, and means for discharging the mixed materials from the container.

4. Apparatus for mixing finely divided materials with a binder, comprising a cylindrical container, a spindle rotatable about an axis in the centre of the container, backwardly raked and inclined blades carried by and rotating with the spindle and extending from the spindle substantially to the inner wall of the container, fixed pressure members carried by the inner face of the container and extending into close proximity to the spindle, and being forwardly curved tothe saidmembers being above, closely adjacent to and co-operating with therotating then a gradually inclined under surface to ward the blades, whereby the materialsmay be first forced to pass up and fall over the blades and then to be squeezed between the blades and the approaching pressure surblades and presenting first an abrupt and 

